Publication Search

Sea transportation plays a crucial role in supporting national development, particularly in transporting goods and passengers. Tanjung Emas Port in Semarang, as a major port with high traffic, faces significant challenges in ensuring navigational safety. This study aims to analyze the partial effects of three key operational factors—Communication System (X1), Safety Facilities (X2), and Crew Competence (X3)—on Navigational Safety (Y). A quantitative approach was used with a sample of 100 ship crew members, selected using incidental sampling. Data were analyzed through descriptive statistics and Multiple Linear Regression (MLR) using SPSS. The results indicate that all three independent variables have a positive and significant effect on navigational safety. The regression equation obtained, Y = -1.398 + 0.218X1 + 0.278X2 + 0.302X3 + μ, shows that Crew Competence (X3) is the most dominant variable in predicting navigational safety outcomes. Collectively, these variables explain 72.4% of the variance in navigational safety. These findings emphasize that human competence and adherence to procedural discipline are critical leverage points in improving safety performance at ports.

This study aims to describe students’ mathematical problem-solving abilities on the topic of Systems of Linear Equations in Two Variables (SPLDV) based on Polya’s problem-solving stages in relation to their levels of self-efficacy. The research employed a descriptive qualitative approach with three ninth-grade students from SMP Negeri 5 Gresik in the 2024/2025 academic year, selected through purposive sampling to represent high, medium, and low levels of self-efficacy. Data were collected using a self-efficacy questionnaire, problem-solving tests consisting of two contextual essay items on SPLDV, and semi-structured interviews. Data analysis followed the interactive model of Miles, Huberman, and Saldana, encompassing data reduction, display, and conclusion drawing, referring to Polya’s four stages: understanding the problem, devising a plan, carrying out the plan, and looking back. The results revealed that students with high self-efficacy were able to complete all four stages comprehensively and reflectively, demonstrating systematic and accurate reasoning. Students with medium self-efficacy successfully performed the first three stages but failed to verify their final results, while students with low self-efficacy only reached the stage of understanding the problem and struggled to plan or execute solutions. In conclusion, the level of self-efficacy influences students’ mathematical problem-solving performance, particularly in terms of strategic accuracy, procedural precision, and reflective evaluation.

This study aims to analyze junior high school students’ mathematical reasoning abilities in terms of their levels of learning independence. The research employed a descriptive qualitative approach involving three ninth-grade students from UPT SMP Negeri 5 Gresik, each representing high, medium, and low levels of learning independence. Data were collected through a self-regulated learning questionnaire, a mathematical reasoning test based on the topic of Systems of Linear Equations in Two Variables (SPLDV), and semi-structured interviews. Data analysis followed Miles and Huberman’s interactive model, consisting of data reduction, data display, and conclusion drawing. The results revealed that students with high learning independence demonstrated strong reasoning skills across all seven indicators of mathematical reasoning (representing statements, making conjectures, performing manipulations, constructing proofs, drawing conclusions, verifying arguments, and identifying patterns). Students with medium learning independence fulfilled only some indicators, while those with low learning independence could only make simple conjectures without systematic reasoning. These findings highlight that learning independence plays a crucial role in developing mathematical reasoning, as it enables students to regulate their thinking processes, evaluate solutions, and correct errors. Teachers are encouraged to integrate learning strategies that foster self-regulation—such as the CORE and Flipped Classroom models—to enhance students’ mathematical reasoning skills.

This study aims to describe the understanding of high school students in solving high, medium, and low category HOTS (Higher Order Thinking Skills) problems and to explore the students' responses in solving problems related to the material of SPLTV (System of Linear Equations with Three Variables). This research is qualitative in nature, using a descriptive method. The subject selection technique used purposive sampling, involving three students from class X IPA/IPS SMAIT Nurul Fajri, with a total of 19 students. The data collection techniques included written tests on mathematical concept understanding using HOTS, interviews, and documentation. Based on the research results, it was found that the students' understanding of mathematical concepts in solving HOTS problems varied. The subject NF-17, with high ability, was able to answer well, including restating the concepts studied in problems 1, 2, and 4, classifying objects based on concepts, applying concepts algorithmically, relating various mathematical concepts internally or externally, providing examples or counterexamples, and presenting concepts in various representations in problems 1, 3, and 4. The subject NF-18, with medium ability, showed more limited results. Although able to restate concepts in problem 4, this subject could only classify objects based on concepts and apply concepts algorithmically in problems 1 and 4. This subject could only provide examples or counterexamples in problem 1. The subject NF-10, with low ability, was only able to restate concepts studied in problem 1 and did not show more in-depth understanding in other problems. These findings indicate variations in students' understanding of mathematical concepts in the SPLTV material.

This study aims to (1) describe the characteristics of e-LKPD based on realistic mathematics education on system of linear equations with three variables oriented towards critical thinking skills and self-efficacy of vocational school students, (2) describe the feasibility of e-LKPD based on realistic mathematics education on system of linear equations with three variables oriented towards critical thinking skills and self-efficacy of vocational school students in terms of validity,  practicality and effectiveness. This type of research is research and development (Research and Development) with the ADDIE model (Analysis, Design, Development, Implementation, Evaluation). The research subjects were 34 students of class X TKP SMKN 2 Tarakan. In this research, One Group Pretest - Posttest Design was used. The research instruments used were validation sheets, practicality assessment sheets by teachers and students, learning implementation observation sheets, critical thinking ability tests and self-efficacy questionnaires. The results of the research show: (1) the e-LKPD developed contains characteristics found in the RME approach to the material of on system of linear equations with three variables oriented towards critical thinking skills and self-efficacy. The characteristics contained in RME-based e-LKPD include integrated learning, use of context, mathematization and construction processes and interactivity. (2) the RME-based e-LKPD developed meets the criteria for feasibility in terms of validity aspects with a percentage of feasibility according to material experts of 93.4% and media experts of 98.9% with the validation result criteria being very feasible; practicality with a very practical category based on the results of student and teacher responses; effectiveness based on critical thinking skills with classical completeness of students reaching 82.4%, the results of the T-test paired samples-test with a significance level of 5% obtained that there was an influence on students' critical thinking skills after treatment using RME-based e-LKPD, the N-Gain result was 0.73 with a high category, and the effectiveness of e-LKPD on self-efficacy with an increase in each self-efficacy indicator,  the N-Gain result was 0.3 in the moderate category, and the results of the Wilcoxon test on self-efficacy data with a significance level of 5%, it was obtained that there was an influence on students' self-efficacy after treatment using RME-based e-LKPD.